Charged particle deflecting apparatus having hemispherical electrodes



Apnl 11, 1967 A. R. WOLTER 3,313,969

CHARGED PARTICLE DEFLECTING APPARATUS HAVING HEMISPHERICAL ELECTRODES 2Sheets-Sheet 1 a a m m m M m 0 U A M m w. 4% 5 JM Filed March 25, 1966INVEN 1 0R. AZ. lA/V R. WO 7296 bY J A r TOZA/EV A. R. WOLTER CHARGEDPARTICLE DEFLECTING APPARATUS April 11, 1967 HAVING HEMISPHERICALELECTRODES 2 Sheets-Sheet 2 Filed March 25, 1966 INVEN'JUR. ALLA/V E.WUL 76E United States Patent" 3,313,969 CHARGED PARTICLE DEFLECTHNGAPPARATUS HAVING HEMISPHERICAL ELECTRODES Allan Roy Wolter, Seattle,Wash, assignor to The Boeing Company, Seattle, Wash, a corporation ofDelaware Filed Mar. 25, 1966, Ser. No. 537,469

2 Claims. (Cl. 313-63) The present invention relates to apparatus havinguse in deflecting charged particles, and, more particularly, to means incombination with apparatus for depositing ions and charged particles ona substrate whereby charged particles in a high current beam of chargedparticles are deflected to impinge at a target substrate.

The instant invention will incorporate the principles of vaporization,ionization, collimation, and deposition of the desired material astaught in United States patent application Ser. No. 438,604, entitled,Ion Beam Deposition Unit, by the inventors Allan R. Wolter, James W. Bieber, Douglas E. Fishkin and Darrell M. Scattergood. Additionally,however, the instant invention incorporates certain novel and importantfeatures to the latte-r patent application.

The manufacture of thin film and semiconductor integratedmicroelectronic circuits presently is accomplished by the condensationof metallic and insulating aggregates of atoms and molecules upon asuitable substrate. Areas upon which condensation occurs are selected bythe use of masks, either in the form of thin stencil sheets orphotographic emulsions. Deposits from the vapor are formed only onunmasked areas. These masks are costly and time-consuming to fabricate.They are diflicult to align in the vacuum chamber where depositionoccurs and they rapidly become so thickly coated with deposits that theymust be discarded. If different thicknesses of one material must bedeposited on a substrate surface, a separate mask must be used for eachthickness. Also, each different material must have its own set of masks.Large metal masks warp away from the substrate, thereby limiting thesize of the circuit capable of being fabricated on a single surface. Theion beam deposition technique, according to the teachings of thisinvention, eliminates the need for masks. The material in the instantinvention which forms the circuit elements is deposited from acollimated beam of ions. The charged nature of the ions allows the size,thickness and position of deposit to be regulated electrostatically andelectromagnet-ically so that no masks are required. A feature of theinstant invention provides convenient and unique means for a focusingelectrode which functions to direct a collimated beam of chargedparticles at a substrate and which does away with the need fordeflection plates in typical ion beam deposition units.

In the present state of art of micro-electronic circuit production,several days may elalpse between initial circuit design and the finishedcircuit. This is necessary because accurate mask layout must be made,the mask must be produced, and each production chamber must be equippedwith the proper combination of masks, substrates and source materials.With the ion beam deposition equipment, any circuit configuration can beproduced with one apparatus; there are no special equipment requirementsfor any circuit. Beam current, particle energy, deposit thickness, andpattern definition, are controlled electronically either by manualcontrol, semiautomatic control, or by a programmed computer. Thus, thetime consumed for a completed circuit is only that time necessary toprogram the circuit parameters into a form acceptable to the computer oroperator and the time required for actual deposition of materials.

When a deposit is made by atomic techniques now in use, the adhesion ofthe deposit film to the substrate is often weak so that the film isunsuitable for use in micro-electronic applications.

It is inherent in an apparatus used for deposition of ions that thephysical distance between the charged partiole focusing electrode andthe collecting surface of the substrate is small, leaving little roomfor deflection means. The instant invention greatly simplifies theproblem of making room for deflection plates by incorporating meanswithin the focusing electrode whereby deflection is insured without needof additional deflection means.

When a deposit is made by atomic techniques now in use, the adhesion ofthe deposit film to the substrate is often weak so that the film isunsuitable for use in microelectronic applications. However, theparticles deposited by the instant invention are sufliciently energeticto remove undesirable surface layers of atmospheric gases, which adhereto substrate surfaces in even very low vacuums, and thus good filmadhesion is insured.

Artificial diffusion can be practiced by the instant invention for avariety of micro-electronic applications Where it is advantageous topenetrate a previously-deposited material with a material diflerent thanthat which was previously deposited. For example, the electricalcharacteristics of semiconductor or dielectric films can be altered byartificially diffusing small quantities of material, commonly calledimpurities, into the material, or the characteristics of metal films canbe altered by artificially diffusing small quantities of metal differentthan the previously deposited metal film, a process commonly calledalloying. The instant invention can, in addition, be used to directlyform films having the characteristics of those films made by theartificial diffusion procedure just described.

The concept of a collimated ion beam, whose current, energy and purityis adjustable, is applicable to any process in which material is to bedeposited in atomic form into or on a surface, or where energy is to bedelivered to a target in a controlled manner. Examples of theseprocesses are: welding or cutting of metals and nonmetals; sensitizationof metal and non-metal surfaces; plating of surfaces; deposition ofinorganic and organic materials; creation of micro-miniature relief mapsor other analogs; creation of patterns, either microminiature or fullsize, which represent stored information such as Braille writing or anyother process of information storage; any process in which an ionizablematerial is to be deposited onto or into a surface; and any process inwhich energy is to be delivered to a collector or target.

If ions or charged particles rather than neutral atoms are utilized inmaking the deposits, the velocity and trajectories of the chargedparticles may be controlled.

It is an object of the instant invention to provide apparatus fordeflecting a collimated charged particle beam so as to impinge onselected portions of a substrate.

Another object of the instant invention is to provide in a focusingelectrode means for deflecting a collimated charged particle beam inaddition to focusing such a beam so as to impinge on selected portionsof a substrate.

The instant invention will incorporate the principles of vaporization,ionization, collimation, deflection and deposition of the desiredmaterials. The control of the beam is to be accomplished in a manneranalogous to the control of electron beams in a cathode ray tube or inan electron beam Welder. This beam, however, will be composed of chargedparticles whose atomic mass is greater or equal to one atomic mass unit.The apparatus will include a chamber of low pressure (partial vacuumchamber) to prevent interference with beam formation and reducecontamination of the resulting deposit by atmospheric gases. Control ofthe apparatus will be accomplished electrically either by manualcontrol, semi-automatic control or by a pre-programmed computer outsidethe vacuum chamber.

The subject matter which is regarded as comprising the instant inventionis particularly pointed out and distinctly claimed in the concludingportion of the specification. The invention, however, will best beundersood by reference to the following description taken in connectionwith the accompanying drawings in which:

FIG. 1 is a block diagram of the over-all components of the instantinvention including interconnecting electrical controls and powersources diagrammatically shown by arrows.

FIG. 2 is a cross-section schematic view illustrating the instantinvention;

FIG. 3 is a perspective view illustrating a feature of the instantinvention;

FIG. 4 is a perspective view showing the instant invention incombination with multiple charged particle sources and multiplesubstrates available so that many circuits of the same or differentdesign or pattern can be produced using any desired combination ofmaterials without replacing or reloading the vapor particle source, orreplacing or reloading the system with new substrates.

Referring now to the figures, like components of the instant inventionhave been given like numeral designations. In FIG. 1, a block diagramrepresents the major components of the instant invention. A means 1 forproducing metal ions or selective charged particles provides a vapor orgas composed of atoms or molecules of the material to be deposited. Themeans 1 includes a vaporizer 1a which produces vapor from a solid orliquid atomic form, or provides vapor from a gaseous atomic form of amaterial to be deposited, and an ionizer 1b which forms ions from someor all of the atomic or molecular vapor or gas which has been formed inthe vaporizer 1a. An ion or charged particle extractor 5 removesparticles from the ionizer 11;, leaving neutral atoms and excludingparticles whose electrical charge is different from the ions desired inthe collimated beam. A beam purifier 7 removes from the ions or chargedparticles formed by means 1 those particles which are not desirable,e.g., unwanted residual gas ions formed in the ionizer lb or otherelement ions, compound ions or charged particles, A velocity controlmeans 9 accelerates or decelerates the charged particles from theextractor 5 electrostatically to a desired velocity. A beam focuser ormomentum selection means 11 electrostatically and/or electromagneticallyselects and forms the charged particles into a fine beam of circular,ellipsoidal, or rectangular cross-section. The beam, a collimated beam,is electrically controlled by the beam focuser 11 so that the large orsmall beam sizes are obtainable when desired. In addition, the beamfocuser 11 functions as a beam positioner and forms means to control theparticle beam direction to a position on the collecting substratesurface at which deposition is desired. This control is accomplished bymechanical movement of the collecting substrate surface andelectrostatic and/or electromagnetic deflection of the ion beam by thebeam focuser 11. A beam neutralizer 15 or means for neutralizing an ionor charged particle beam forms neutral atoms or molecules from thecharged particles in the collimated beam. A collecting substrate surface17 is the surface on or into which the material is deposited. Electroniccontrol means 19 and 21 are electrically connected wtih the means 1through 17. The electronic control means 19 and 21 control: quality andtype of material vaporized in the vaporized means 1a; the quantity ofvapor in the ionizer 1b; the magnitude of beam cur-rent; the purity ofthe beam realizable in beam purifier 7; the geometric charged particlebeam cross-section; the velocity of ions in the beam determined by means9; the position, geometry, and quantity of the deposit, and the degreeof vacuum established in the partial vacuum chamber. The electroniccontrol means 19 and 21 are capable of preprogramming to allow theentire procedure to proceed automatically to complete the desireddeposit. The entire procedure is also capable of manual orsemi-automatic control. Electronic control is capable of accepting froman operator, instructions for controlling different deposit geometries,different charged particle energies, different beam purity andcomposition, and different deposit electrical characteristics.

The functions outlined and defined in general terms above need not beseparate and distinct. One or many functions may be accomplished in onesingle operation in a device using the ion beam principle. Also, thefunctions of an ion beam device need not be in the order of the abovedescription and need not be restricted to ion beams alone but rather mayencompass any charged particle beam. Referring to FIG. 2, theconfiguration of the over-all combination of the instant invention isshown. Several different types of vapor source means 2 can be used tosupply atomic vapor: an alumina or other refractory crucible wrappedwith resistively heated tungsten wire; a tantalum boat resistivelyheated; an alumina or other refractory crucible heated with an electrongun or other means of electron or ion discharge; and direct electronbombardment of refractory materials in an aluminaor other refractorycrucible are a few examples. Means 4 disposed to direct a discharge ofenergetic particles such as electrons at said vapor source means 2 may,for example, comprise an ionizing filament 4 made of 20 mil tantalumwire wound in a bi-filar spiral of approximately one-quarter inchdiameter or any electron emitting filament which is sufficiently smallto be contained in the space provided, such as a rectangular grid, or acircular coil formed from one or many turns of wire, or a point filamentformed by a single bend in a single wire. Means 4 is separated duringoperation approximately one-quarter inch above a vapor source material 6and approximately one-half inch below a heat reflecting cover hood 8.The ionizing filament 4 is given a negative potential with respect tothe source material 6 and the plasma cover hood 8, by connecting a leadfrom filament support 30 with a unipotential voltage source 18.Porcelain insulators 32, attached to frame 34 by bolts 36, supportfilament support 30 and hood 8. Frame 34 is welded to heavy supportframe 38. When the vapor source means 2 is not heated, a current of tenamperes through the ionizing filament 4 produces a pure electron flowtoward the source material 6 of approximately ten milliamperes. Circuitmeans 28a connect vapor source means 2 with a voltage source 28; as thevapor source means 2 is heated using current from source 28, the sourcematerial 6 vaporizes. Vapor is directed upward toward the ionizingfilament 4. Ionization of atoms in the vapor is accomplished bycollision with electrons flowing from the ionizing filament 4. Thedevice will now produce ions which can be extracted by the ion extractor5 and used in the instant invention. The rate of ionization is increasedby the addition of a magnetic field about the plasma which forms betweenfilament 4 and vapor source 2. Such a magnetic field is generated by amagnetic field means (not shown; but, for example, a solenoid) disposedaround the means for selectively producing pure ions 1. The magneticfield means (not shown) is energized by any voltage source sufficient toprovide a magnetic field within means 1, about the plasma as notedabove, strong enough to cause spiralling of the electrons but not theions. The spiralling effect allows the electrons to travel a greaterdistance between filament 4 and vapor source means 2 than otherwise isthe case. The magnetic field produces a pinch effect upon the plasma,thereby increasing the density of the plasma in which ionizationoccurs'due to energetic particles from filament 4 colliding with atoms,within the plasma, from vapor source means 2. The total effect, as notedabove, increases the rate of ionization.

In construction of the magnetic field means (not shown) about the means1, certain requirements must be met that can be considered withreference to FIG. 2 even'though the magnetic field means is notillustrated. The magnetic field means (not shown) must be of suchgeometrical configuration that the apertures, e.g., vapor source andionizer assembly opening 13, and the immediately opposed opening inhemisphere 10 are not obstructed, and that the mechanical function ofthe means 1 and the extractor assembly 5 is not interfered with. Inaddition, the axis of the coil of magnetic field means (not shown) mustbe oriented parallel to the direction of the discharge from filament 4to the source material 6; i.e., the coils must be so oriented withrespect to means 1 that the direction of the magnetic field is orientedparallel to the direction of the discharge from filament 4 to sourcematerial 6.

' Continuing with reference to FIG. 2, the ion extractor assembly 5consists of two tantalum hemispheres 10 and 12, with radii of curvatureof one and one-half inches and one-half inches, respectively. Holes of.234 and .125 inch,

respectively, were bored in the center of the curvature of thehemispheres 10 and 12. The larger hemisphere 10 is placed with its.234-inch hole just opposite the ionizing filament 4 and one-quarterinch in front of the vapor source and ionizer assembly opening 13. Thehemisphere 10 is electrically grounded, or at a voltage nearer zero thanhemisphere 12, by means of a lead connecting hemisphere 10 to a voltagesource 28. The smaller hemisphere 12, placed concentric to the largerhemisphere 10, is operated at a high negative potential, also derivedfrom voltage source 28, ranging from 1000 to -15,000 volts with respectto the larger hemisphere 10. Approximately 5,000 volts are usually used,since at this voltage suflicient ions are extracted and no breakdownproblems are encountered. The electric field thus set up by the ionextractor assembly 5 (hemispheres 1t) and 12) extract ions from theplasma existing inside the vaporizer and ionizer assembly 1 andaccelerates them toward the smaller hemisphere 12 due to the highnegative potential existing there with respect to hemisphere 10. Theelectric field configuration is such that the ions partially focus and alarge portion of them pass through the hole in the smaller hemisphere1.2 of the ion extractor assembly 5.

An electrostatic beam focus 11a, which also functions as a deceleratorand velocity control unit, is composed of two tantalum hemispheres 14and 16. In the beam focus 11a, the smaller hemisphere 14 is placed inelectrical contact with the smaller hemisphere 12 of the ion ext actor 5and is therefore at the same negative voltage. The large hemisphere 16of the beam focus 11a serves both as an ion lens system and anelectrostatic deflection means and is sectioned into four eoualquadrants (as best seen in FIG. 3); each quadrant is insulated from allthe others by any suitable insulation means 41, and each quadrant isconnected in a predetermined manner by a lead to potential differencemeans or voltage source 28 and 18 as will be described below withreference to FIG. 3.

By this sectioning and selective voltage application, hemisphere 16accomplishes beam focusing, energy adjustment, and deflection of the ionbeam (the latter function being discussed more fully below). Thevelocity of the ions can be controlled by the potential derived fromvoltage source 28 on the sectioned hemisphere 16. The velocity, in turn,determines the position at which the ion beam reaches its minimum focaldiameter. Zero, negative, and small positive potentials from source 18on the hemisphere 15, with respect to ground, have been usedsuccessfully. The voltages applied to the ion extraction hemisphere 12,and the ion decelerator, velocity control, ion focus and beam deflectionhemisphere 16 relative to the ion source and'vaporizer assembly 1 areestablished by the unidirectional voltage source 23.

The position of ion impingement as a collimated beam upon a substratecollecting surface 17 is regulated by electrostatic deflection and bymechanical movement of the substrate 17. Electrostatic deflection isaccomplished by the use of the sectioned hemisphere 16. Referring toFIG. 3, the applied electric potentials to hemisphere 16 establish anelectric field which deflects the ions from their normal path. This isaccomplished by applying a unipotential voltage to electrode quadrantsa, a, b, and b of sectioned hemisphere 16 from voltage source 28 as wellas a variable directional voltage to electrode quadrants a, a, b, and bof hemisphere 16 from voltage source 18.

The beam of ions from ion extractor 5 passes through a central apertureor opening 40, defined by electrodes a, a, b and b, of hemisphere 16(shown in FIG. 3). The ion beam has an energy which is determined by theaverage voltage upon the four quadrants of hemisphere 16, i.e.,

I I V average: 1 +Vb where V V V and V represent the total voltage onquadrants a, b, a and b respectively.

To accomplish deflection of the ion beam having an energy determined byV average without distortion of the ion beam, an equal but oppositevoltage V is applied to opposite quadrants, viz., set a-b and a-b. Thevoltages on opposite quadrants a, b will be as follows:

V V average V V V average- V Thus the ion beam will be deflected towardquadrant bbut the energy and focal length will be unaffected.

Similarly, the voltages on opposite quadrants a, b will be as follows:

V '=V average +V V =V average V and the ion beam will be deflectedtoward quadrant b with no effect upon ion beam energy and focal length.The two sets of quadrants can now be used to draw any configurationdesired upon the substrate 17 of FIG. 2 and FIG. 4.

The voltage V can be either A.C. (variable directional) or DC.(unipotential) depending on whether one wishes to scan the beam over aline or simply deflect the beam to a new position, respectively. Thismethod of a plying voltages is not new and is used in almost allelectrostatic deflection schemes, commonly termed a push-pull voltagearrangement. However, the application of such a voltage arrangement witha sectioned lens system as hemisphere 16 is new. Since some impure ionsare of different energy than the desired ions while also being of adifferent mass than the desired ions which are to be deposited onsubstrate 17, (that is, those ions not generated within means 1), theyare deflected away from the position of the deposition; that is, themore massive particles are deflected less than the deposit ions; lessmassive particles are deflected more than the deposit ions. Thus,electrostatic deflection accomplishes two functions: beam deflection andfurther beam purification.

It is to be understood that the electrostatic deflection electrodes(quadrants a, a, b, b'),of FIG. 3 find utility in any apparatus usingcharged particles and more specifically with apparatus using electronswhere the electron beam serves useful functions such as cutting,heating, welding, information storage or any other application whereinan electron 'beam interacts with a surface. In such applications asthese the object is not to deposit material upon a substrate but ratherto direct charged particles, by means of the lens system (hemisphere 16)of FIG. 3, at any desired surface. 1

Continuing with reference to FIG. 2, mechanical movement of thesubstrate 17 is achieved by conversion of a jewelers lathe compound 25(that unit to which the cutting tool is normally attached and whichcontrols the motion of a tool by means of two vernier knobs). Allstandard lubricants are removed from the lathe 25 and replaced withvacuum lubricants. The movement knobs (shown only diagrammatically inFIG. 2 as 22) are removed and two stepping switches (not shown) aremounted face-to-face on each movement shaft. Thus, the collector surfaceof the substrate 17 can be moved by external (not shown) electricalactivation of the stepping switches (not shown), or by manualactivation.

The ion beam should be neutralized immediately before or during impactwith the collecting surface 17 so that succeeding ions will not berepelled by charge buildup. This is accomplished by bathing thecollecting surface 17 with electrons from an incandescent filament 15awhich is connected to the power source 18. This neutralizing filament15a forms the beam neutralizer of the instant invention and can be madefrom 20 mil tantalum wire bent into the shape of a circle about the samediameter as the hole 40 in the decelerator hemisphere 16, for example.With this neutralizing filament 15a placed about one-eighth of an inchaway from the collecting surface of substrate 17 and concentric to thecollimatecl ion beam, it is possible to deposit a nonconducting layer onnonconducting substrate surfaces 17.

As discussed above and presented here in summary, the ion beam current(collimated beam) is capable of control by several means: an increase insource heat by vapor source means 2 results in increased vapor densitywhich, in turn, will result in a more dense plasma at the ionizingfilament 4; a higher negative voltage on the small hemispheres 12 and 14results in more ions being removed from the plasma with concomitantstronger focusing so that more ions pass through the holes in the smallhemispheres 12 and 14; a greater negative voltage on the largehemisphere 16 of the decelerator, focusing and deflecting assembly 11a,which minimizes ion loss, results in more deposition on substrate 17. Anoperator has the option of choosing which control he will vary in orderto change the ion current. The most convenient means to do this is byregulation of the source heat to the vapor source means 2.

The entire apparatus as described in FIG. 1 and FiG. 2 is mounted in apartial vacuum chamber 23, having a vacuum pump 24, defined by dashedlines and shown in FIG. 4. A pressure within the vacuum chamber 23 ofmm. Hg is maintained during most operations of the device. The apparatushas an approximately eight cubic foot volume and is evacuated by asix-inch oil diffusion pump 24 having a liquid nitrogen cold trap backedby a -cubic-foot-per-minute holding pump (not shown).

The ultimate design of the invention will take many different formsdepending upon the specific application. For productiOn ofmicrocircuits, an embodiment of the ultimate design is shown in FIG. 4to be described below.

Referring to FIG. 4, since any thin film or semiconductor integratedcircuit is generally made from several different deposited materials,means must be provided for several different ion source assemblies 1, asshown in FIGS. 1 and 2. Multiple ion source assemblies 1 can be madeavailable to the ion beam device by several different means. One examplewould be to place several separate and distinct ion source assemblies 1upon a table which can be rotated mechanically. Each ion source assembly1 could produce ions of a different type from all the remaining, orseveral ion source assemblies 1 could produce the same type of ions sothat the ion beam device would be long lived for any initial setup. Asecond example (not shown) of providing multiple ion source assemblies 1would be to use a single source of energetic particles while a rotatabletable disposes several different vapor sources and vapor sourcematerials into proper position with respect to the source of energeticparticles. Many other means by which the vapor source means 2, vaporsource material 6, ionizer filament 4 and cover hood 8, as shown in FIG.2, can be combined so as to form the ion source assembly 1, whether asseparate and distinct parts or as part of assemblies, can be devised.Ionization will be accomplished using the arc discharge 8 principle asdescribed above. The type of vapor source means 2 will be dictated bythe type of vapor material 6 to be vaporized.

Continuing with reference to FIG. 4, the ion extractor 5 removes ionsfrom the ionizer and vaporizer assembly 1; the beam focuser anddecelerator velocity and deflection control unit 11a brings the ions toa desired velocity and forms them into a collimated beam. The deflectionfunction of hemisphere in acts as a final beam positioner (and as a lastion beam purifier) to direct selected ions toward a focus in the planeof the substrate surface 17. As seen with reference to FIGS. 2 and 3,the hemisphere 16 is operated as an electrostatic deflector. Other meanssuch as electromagnetic coils could also be used.

In the embodiment of PEG. 4, may different substrates 17 areconveniently disposed to receive ion deposition. Several substrates 17are placed circumferentially upon a turntable 20a, which is rotated bymechanical drive means (not shown). The desired substrates 17 can thuseasily be disposed to receive ion deposition.

The requirements which must be fulfilled by the new tralizer 15a is thatit supply to the substrates 17, large quantities of low energy electronsto efficiently neutralize the ions being deposited while at the sametime not interfering with the ion beam definition. This can beaccomplished by using as neutralizer 15a a flood electron gun whichindiscriminately sprays the entire substrate surface 17 with largequantities of electrons. Other means (not shown) will suflice: by anelectron filament located near the substrate, or by an electricallygrounded conductive layer deposited on the substrate prior to the use ofthe instant invention, or by starting deposition at a point which isgrounded so that as deposition proceeds, the deposit itself neutralizesthe charge. The substrate material or collective surface 17 can be anymaterial usefiil in the microelectronic art. For example, silicon wafersare often used for producing integrated circuitry, while insulating ormetal substrates are often used for thin film circuit production. Toenable more than one circuit to be made during one chamber evacuation, amultiple substrate changer and storage mechanism may be included. Thisdevice would be capable of placing the substrate 17 into the desiredposition for deposit, removing the completed circuit from the depositregion and reloading the device with a new substrate. As mentioned inthe discussion of FIG. 4, the vacuum chamber 23 will be evacuated by avacuum facility 24, such as a mechanical pump ganged with oil or mercurydiffusion pumps or by any other vacuum pumping apparatus. The vacuumchamber 23 will be large enough to contain the device components, beequipped with pressure sensing devices (not shown), such as anionization pressure gage, and possess sufficient electricalfeed-throughs to external controlling mechanisms (not shown).

The over-all control unit shown in FIG. 1 as 19 and 21 is an inputdevice which reduces idea to form: i.e., the various constants necessaryto deposit the required amounts of material at predesignated locationson the substrate 17 and in the proper sequence originate from this unit.The control unit 19 and 21 may consist of manual, semi-automatic, orautomatic control. The control can be connected to several independention beam deposition devices to increase the number of microelectroniccircuits which are produced for any sequence of input commands.

Instead of the spherical sectioning of hemisphere 16 to accomplishfocusing, beam deflection, and energy adjustment, the effect is the sameif the quadrants of 16 are approximated by plane sections arranged toform a truncated pyramid of square cross-section.

Since numerous changes may be made in the above apparatus, and differentembodiments may be made without departing from the spirit thereof, it isintended that all matter contained in the foregoing descriptionreferring to apparatus or shown in the accompanying drawings shall beinterpreted as illustrative and not in a limiting sense.

I claim:

1. Apparatus for focusing and deflecting a beam of charged particleshaving a predetermined average velocity comp-rising:

(a) four electrodes defining and forming a sectioned hemisphere, each ofsaid four electrodes forming a quadrant of said sectioned hemisphere andeach of said four electrodes being joined one to the other by insulatingmeans so that said four electrodes additionally define a centralaperture in said sectioned hemisphere, said sectioned hemisphere beingpositioned concentric about the path of the beam of charged particlessuch that the beam of charged particles passes into the volume enclosedby said sectioned hemisphere and then passes through said fourelectrodes defined central aperture of said sectioned hemisphere; and

( b) potential difierence means connected to each of said fourelectrodes such that opposite quadrants of said sectioned hemisphere areof opposite potential polarity so as to create an electrostatic fieldWithin the volume enclosed by said sectioned hemisphere for focusing thebeam of charged particles and said potential difierence means creatingan electrostatic field across said four electrodes defined centralaperture such that the focused beam of charged particles, in passingthrough said four electrodes defined central aperture, will be deflectedto conform to a selected pattern without effect upon beam energy.

2. In combination with apparatus for depositing metal coatings uponselected portions of a substrate having means for producing a collimatedbeam of metal ions and velocity control means associated with said firstmentioned means for developing a flow of metal ions in the collimatedbeam of a predetermined average velocity, the means forming an ion lenssystem and an electrostatic deflection means comprising:

(a) four electrodes defining and forming a sectioned hemisphere, each ofsaid four electrodes forming a. quadrant of said sectioned hemisphereand each of said four electrodes being joined one to the other byinsulating means so that said four electrodes additionally define acentral aperture in said sectioned hemisphere, said sectioned hemispherebeing positioned concentric about the path of the collimated beam ofmetal ions such that the collimated beam of metal ions passes into thevolume enclosed by said sectioned hemisphere and then passes throughsaid four electrodes defined central aperture of said sectionedhemisphere; and

(b) potential diiference means connected to each of said four electrodessuch that opposite quadrants of said sectioned hemisphere are ofopposite potential polarity, said potential dilference means creating anelectrostatic field Within the volume enclosed by said sectionedhemisphere for focusing the collimated beam of metal ions and saidpotential difference means creating an electrostatic field across saidfour electrodes defined central aperture such that the focusedcollimated beam of metal ions, in passing through said four electrodesdefined central aperture, will be deflected to conform to a selectedportion of the substrate Without effect upon beam energy.

References Cited by the Examiner UNITED STATES PATENTS 2,143,580 1/1939Ruska 313-76 2,919,381 12/1959 Glaser 313-77 3,042,832 7/1962 Owren 31378 3,231,830 1/1966 Knaver 313-161 X 35 JAMES W. LAWRENCE, PrimaryExaminer.

S. D. SCHLOSSER, Assistant Examiner,

1. APPARATUS FOR FOCUSING AND DEFLECTING A BEAM OF CHARGED PARTICLESHAVING A PREDETERMINED AVERAGE VELOCITY COMPRISING: (A) FOUR ELECTRODESDEFINING AND FORMING A SECTIONED HEMISPHERE, EACH OF SAID FOURELECTRODES FORMING A QUADRANT OF SAID SECTIONED HEMISPHERE AND EACH OFSAID FOUR ELECTRODES BEING JOINED ONE TO THE OTHER BY INSULATING MEANSSO THAT SAID FOUR ELECTRODES ADDITIONALLY DEFINE A CENTRAL APERTURE INSAID SECTIONED HEMISPHERE, SAID SECTIONED HEMISPHERE BEING POSITIONEDCONCENTRIC ABOUT THE PATH OF THE BEAM OF CHARGED PARTICLES SUCH THAT THEBEAM OF CHARGED PARTICLES PASSES INTO THE VOLUME ENCLOSED BY SAIDSECTIONED HEMISPHERE AND THEN PASSES THROUGH SAID FOUR ELECTRODESDEFINED CENTRAL APERTURE OF SAID SECTIONED HEMISPHERE; AND